Star notes form a collecting specialty. Value can range from near par to over $1,000 (retail). For example, a 1934 $50 Minneapolis star bill in Unc-63 is worth about $1,300 retail. The combination of rarity, condition and demand create these premium values. Slightly older, a 1928 Dallas star bill is retail valued at $8,000 in Unc. 63. Reviewing "Completed transaction" on Ebay is a way to get an idea of what the market is actually paying--but, of course, one sale does not constitute fair market value though it's an indicator.
Don.....
(Source: The Official Red Book: A Guide Book of US Paper Money)